A Fast and Accurate Method of Synthesizing X-Wave Launchers by Metallic Horns

This paper presents a method for synthesizing metallic horns capable of radiating highly localized electromagnetic pulses, known as X-waves. The proposed method is based on a mode-matching framework for shaped horns. The aperture field distribution required to generate X-waves is synthesized by mode conversion. The near-field horns generated by this method are full-metal structures radiating X-waves in a wide range of frequencies with low dispersion. The obtained structures may be scaled to any frequency range, and they are particularly suited to millimeter and sub-millimeter wave applications. We validate the concept by presenting a horn capable of radiating X-waves over a 44% fractional bandwidth (FBW) with a 5° dispersion of the axicon angle. Capabilities and limitations of this design procedure and the synthesized launchers are demonstrated, discussed, and compared with other state-of-the-art solutions.